How to Extend Raid 5 Array or Partition in Windows

Jean updated on Sep 12, 2019 to Partition Master | How-to Articles

Why Need to Expand/Extend Raid 5

Case 1: "I have a Highpoint Rocket RAID 454 for Windows XP SP2 and 2000 SP4 (+Rollup). One array is RAID-5 with three disks, and I would like to add another disk to this array. I know I can add a new disk if the array is broken but how would I 'expand' an existing (working) array without data loss?"

Case 2: "I have ML 350 G5 Server with 3 Hard disks currently configure RAID 5. My Question is here:Can I add New Hard Disk without destroying my current data and OS if so? What is the utility I am going to use?"

Case 3: "I've got a Compaq ML370G2 with three drives in a RAID5 array connected to a 5i controller. How do I go about adding a 4th drive to the array? Is there an application like in NetWare (cpqonlin.nlm) to do this?"

Have you ever come across the above cases that the Raid is out of space? Generally, the purpose of expanding the Raid 5 partition is to maximize the performance of server computers by having more disk space on Raid 5.

Solutions for Extending/Expanding Raid 5

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 Server 2016 is supported

Solution 1: Use Raid Array Partition Software to Extend/Expand Raid 5 Array

If the Raid controller support to expand Raid 5, you need to insert a new hard disk into the existing hardware Raid and organize this Raid using Raid controller.

Some unallocated space will appear on this Raid. Install the Raid partition software - EaseUS Partition Master Server and then resize the Raid partition with the unallocated space. The problem of how to resize/extend Raid 5 array in a safe way will be effortlessly solved.


Step 1: Launch EaseUS Partition Master

Run partition manager software

Step 2: Free up space to extend partition

If the hard drive has enough unallocated space to extend the target partition, jump to Step 3 and continue.

If not, free up space first:
1. Right-click on a partition next to the target partition and select "Resize/Move".
2. Drag the partition ends to free up space, leaving enough unallocated space behind the target partition, click "OK".

Free up space to extend partition

Step 3: Extend partition

1. Right-click on the target partition and select "Resize/Move".

Resize target partition

2. Drag the target partition handle into the unallocated space to extend partition.

Add space to the target partition

Step 4: Keep all changes

Click the "Execute Operation" button and click "Apply" to keep all changes.

Keep all changes for extending partition

Solution 2: Use a Highpoint Controller

Unless the highpoint controller which provides a Raid expansion feature, there isn't any direct methods for you to expand Raid 5 array.

Solution 3: Add Extra Drive

The other way is to first backup data on Raid 5. Then delete the 3 drive array and re-create it as a 4 drive array. Then break the Raid array, connect the new disk to the computer and recombine the Raid 5 array by using the Raid controller with all the disks you want to utilize. Restore the data to the new larger Raid 5 array.

Note: If you add a disk that's larger than the other disks, it will be resized to match the capacity of the others. For example, if you have three 80 GB disks and add a 160 GB disk, you will only be able to use 80 GB of the 160 in your new configuration. The rest space of the drive will be unusable. So the Raid 5 copy software is your best choice.


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Frequently Asked Questions

Why Choose EaseUS Partition Master?

"I've used Partition Master Professional many times to create, delete, format, move, rename, and resize partitions."PCWorld

"Partitioning tools have come a very long since the days of complicated command line utilities and EASEUS Partition Master is one of the most advanced programs available."TECH ADVISOR

"I love that the changes you make with EaseUS Partition Master Free aren't immediately applied to the disks. It makes it way easier to play out what will happen after you've made all the changes."Lifewire

Will the "Migrate OS" feature transfer the Windows system files only or the whole C drive?

To ensure that the migrated system will boot normally, the Migrate OS feature will transfer all the files in the system and the boot partitions. Generally, the boot partition is the C drive so the transfer will include all the files in C.

Does EaseUS Partition Master license apply to multiple computers?

The license of Partition Master Professional and Server editions can be used on 1 computer only, while that for for the Technician and Unlimited editions can be used on multiple machines.

What is the difference between EaseUS Partition Master Trial version and the Free version?

Free is for home users only, with most basic functions available such as partition resize and clone. While trial can help you understand how this product works and test what a full license can do on a business or server OS machine.

Will it cause any data loss after resizing the partition in EaseUS Partition Master?

Generally, it will not cause any data loss or boot issue by resizing a partition. However, in order to protect your data, we suggest that you backup the partition before resizing, in case of any unexpected situations such as power outages, computer hardware failures, etc. You can use EaseUS Todo Backup to backup the partition and its trial version is fully functioned for 30 days.

What should I prepare before resizing the partition?

On the partition that is going to be operated, there might be some files being occupied by other programs. To ensure a successful operation, we suggest that you close all the unnecessary software before resizing that partition. Otherwise, EaseUS Partition Master will detect the partition being locked by the other software and require a reboot to resize the partition under boot mode.

About EaseUS Partition Master

All-round disk & partition management software for personal and commercial use. Let it manage your storage drive: resize, format, delete, clone, convert, etc.